﻿/*
 Copyright (c) 2007 Eric J. Feminella  <eric@ericfeminella.com>
 All rights reserved.

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is furnished
 to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in all
 copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
 INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 @internal
 */

package com.ericfeminella.utils{
	import flash.errors.IllegalOperationError;

	/**
	     *
	     * All static class which provides an API for enforcing an pseudo
	     * abstract class is never to have an instance instantiated
	     *
	     * @example The following example demonstrates how to utilize
	     * <code>AbstractEnforcer</code> to ensure a pseudo-abstract
	     * class is never instantiated
	     *
	     * <listing version="3.0">
	     *
	     * package
	     * {
	     *   import com.ericfeminella.utils.AbstractEnforcer;
	     *
	     *   public class Abstract
	     *   {
	     *       public function Abstract()
	     *       {
	     *            AbstractEnforcer.enforce(this, Abstract);
	     *       }
	     *    }
	     * }
	     * </listing>
	     *
	     * @see flash.utils.getQualifiedClassName
	     *
	     */
	public class AbstractEnforcer {
		/**
		         *
		         * Provides a mechanism for enforcing a pseudo-abstract class
		         * is never instantiated
		         *
		         * <p>
		         * When an attempt to instantiate an instance of an Abstract
		         * class is made an exception is thrown as the instance constructor
		         * is checked against the Class type which has been specified.
		         * </p>
		         *
		         * @param instance which is to be compared against the abstract type
		         * @param abstract type which is to be compared against the instance
		         *
		         */
		public static function enforce(instance:Object,type:Class):void {
			if (instance.constructor==type) {
				throw new IllegalOperationError(type+" is an AbstractClass and can not be instantiated");
			}
		}
	}
}